Book-check



F. P. ANGELL..

nooR CHECK.

' APPLICATION FILED MAR. 23,.' 19|?. 1,309,056.

Patented July 8, 1919 FRED r. ANGELI., or'BATTiiE GREEK, MICHIGAN.

Specification of LettersfPatent.

Application filed March 23, 1917. Serial No. 156,866.

l tion, the principles of the invention being therein explained and the best mode I have contemplated for applying that principle, so as to distinguish it from other inventions for a similar'purpose. f v

This invention relates to door checks, and

vmore particularly refers to door checks in which the cushion is affected'by the compression of air and the reaction by meansof a coil spring acting on a piston, the rod of which forms an uneven-faced rack engaging a segmental eccentric-sliaped `gear on the axle on which the door operating arm is fitted, a check valve being fitted between the piston and its actuating rod in such manner that vacuum will not hinder the check from readily responding in Openinga door, yet furnish sufcient cushion in combination with the peculiarly designed piston and cylinder to allow the door to move slowly and silently when making its final closure.

Among other objects, the present invention contemplates a door check of the character set forth that will be compact and neat in appearance, positive and silent in operation, and one that can be manufactured at a minimum expense. Tothese ends the invention consists in the combination and arrangement of parts as will hereinafter be more fully described, shown in the accompanying drawings and defined in the appended claims, it being understood that changes in the form, proportion, material. and minor details may be resorted to with-l out departing from or sacrificing any of the advantages thereof.

In the drawings, Figure 1' is aside elevation of the door check applied to a door and its casing.

' Fig. 2 is an end view of a door and its casing with the door check attached, the door being partially open.

Fig. 3 is a broken side elevation of the door check withits piston inI a relaxed posi* tion, and as it would appear before opening a door.

Fig. 4 is a longitudinal vertical section.

Fig. 5 'is a detail, broken section of the by-pass and its regulating needle valve.

Fig.. 6 is aperspective view of theV piston attaching stud. l

Like marks of reference refer to corresponding or equivalent parts throughout theV different views, in which A represents a door; B, a door casing; and C, the check valve cylinder suitably attached to the door by means of screws through legs l forming a part of the cylinder casting.

'The piston head 3 is arranged Within the cylinder facing its removable closed head 2. This piston head is formed with a centrallybored externally-threaded shank 4l, around which the piston sucker or bushing 5 and its resilient expanding ring 6 are placed, the bushing .lying against the head with its curved rim flaring toward the cylinder head, the resilient ring 6 in turn being held against said bushing by an adjusting rimmed nut spreader 7 fitted to the shank 4. The object of the aforesaid arrangement is vto variabl y expand the piston bushing 'by turning the nut on the shank of the piston head, a. vmeans whereby wear not interfere with its proper working. The ring may be of rubber, a coil of wire, or equivalent that will answer the purpose. The piston head as aforesaid arranged is fitted to a concentrically-disposed end of a rack-faced piston rod 8 by means of a flanged-headed stud 9 screw-threaded into the end `of the piston rod.

Between the end ofthe piston rod and a shoulderof the stud 9 a ouppeddisk l0 is fitted, and about said stud within the cupped surface of said -disk and a cupped-outsurface of the iston-head 3, a flexible ring valve l1 is pllaced. This valve checks the escape of air in the space between the piston sucker 5 and the cylinder head 2y in the final closing of a doorby stopping a passage or vent 13 leading from saidispace through thestud 9'to a chamberbetween the cupped surfaces of thedisk 1,10 and piston head 3, more especially after the piston has moved beyond a by-'pass v12 leading from a point in close proximity to the-rear of the piston intov the cylinder to the rear of said piston when at its rearward stroke. The closing of the vent 13 iseffected by compressingthe valve 11 between vthe cupped'surfaces of the` disk lO and piston-head 3 by the sliding of the piston 5 on the stud 9 from air compression in the cylinder on the one hand, andthe action of a spring '17 effecting an opposite movement to the piston rod and the disk 10 y Patented July 8, 1919*.

of said vbushing willv thereon, a reversal of the movement in the opening of a door releasing the Vent and displacing any vacuum in the cylinder.

That the final closing of the door may be further facilitated, the cylinder is slightly funnel shaped at the endewhere the head 2 is screwed on, and as the piston sucker 5 nears the limit of its movement, compression in the cylinder is slightly reduced, yet having suicient resiliency to ease the movement of the door in entering its jamb.

Fitted to intercept or regulate air through the byfpass 12, a needle valve D is screwthreaded into a boss formed on the cylinder for the purpose.

The piston adjusting collar 14 is fitted to slide on the concentrically disposed end of the rack piston rod 8. This collar is cupped, as at 15, where it faces the ring disk 10, so that whenmoved to its outward limit on the piston rod the disk 10 and said collar will be in alinement. Encompassing the piston rod and bearing against a rib 16 forming a guide-bearing for said rim of he collarv 14, the coil-spring 17 is placed, its object being to return the piston to a normal position and close the door.

That the tension of the spring may be varied to meet conditions in the closing of a door, and still permit the piston to always move its full sweep in the cylinder, the piston rod is provided with a longitudinally-disposed hole to the side of its axis opposite its rack surface and fitted with a screw 18, the threaded end of which is screw-threaded into the movable collar 14.

The rack or toothed surface of the piston rod engages with the teeth of a segmental cam-shaped gea-r 20 arranged to one side of the piston, one end of its shaft 21 being seated in a removable screw-threaded bearing 22 fitted into a boss of the cylinder C, its opposite end extending through a serewthreaded lbearing 23 in a boss on the opposite side of the cylinder and fitted with an arm 24, the arm 24 being hinged to a variably extensible arm 2,5 hinged to the door casing in the usual mannen The teeth on the piston rod are arranged 1n an 'irregularfac'ed manner, terminating in a. raised uniform surface toward the piston extremity, for the purpose of geared contact with the cam-shaped segmental gear 20, the free end of the rack meshing with the gear 20 at its greatest circumferential throw, at which position the door is closed, an object in connection with the check valve. 11 being not only to reduce the momentum of the door Copies of this patent may piston rod andV the that the piston rod 8 may have sufficient n movement, and yet be covered Vwithout extending the cylinder itself for the purpose.

It will be obvious that by unscrewing the head 2 from the cylinder C the mechanism may 'be removed or replaced, as occasion may require, without taking the check from the door, an object of importance in mechanism of the character.

From the foregoing description taken in connection with the drawing, a more ex tended explanation of the operation and advantages off my invention is believed to be unnecessary.

Having, therefore, described my invention, what I claim as new .and desire to se cure by Letters Patent, is zi 1. A door check, the combination of the cylinder, its head, a piston closing said cylinder and the piston rod attached to said piston, of the guide for said piston, a tension collar on said piston, the `spring fitting between said guide and collar, and a screw passing through an offset of said piston rod into said collar for regulating the tension of said spring, substantially as specified.

2. In a door check, the combination with the cylinder, its head, a piston closing said cylinder and a piston rod slidably fitted through said piston, of means to limit the movement of said piston on said piston rod, an annular cupped offset formed in said piston, an annular cupped offset formedin said piston rod, and a iexible ring valve interposed between the cupped surfaces of said piston rod and piston about a reduced portion of said piston rod, said piston rod having:an opening leading from the space between its offset and said piston to the space between said piston and the closed head of said cylinder, -a and for the purpose set forth.`

FRED P. ANGELL. Witnesses:

V.l L. GRAssMAN, PAUL NONEMAN.

be, obtained for vecents each, by addressing the commissioner of Patents, A Y

Washington, D. G. 

